Guide means for fasteners intended to be fired with explosively actuated power-tools



Oct. 19, 1965 c. ROSSELET 3,212,333

GUIDE MEANS FOR FASTENERS INTENDED TO BE FIRED WITH EXPLOSIVELY ACTUATED POWER-TOOLS Filed Jan. 10, 1963 Fig.

In van for (1/1 UDE ROSSELET A/fomeys United States Patent GUIDE MEANS FOR FASTENERS INTENDED TO BE FIRED WITH EXPLCBSIVELY ACTUATED POWER-TOOLS Claude Rosselet, Founex, near Nyon, Switzerland, assignor to Sarmi S.A., Societe dApplications de Recherches Minieres et Industrielles, Lenzerheide (Grisons), Switzerland, a Swiss company Filed Jan. 10, 1963, Sr. No. 250,660 Claims priority, application Switzerland, Jan. 17, 1962, 530/ 62 1 Claim. (CI. 85-10) The problem of perpendicularity of fixing of sealing elements such as pins, nails, etc. which are fired into a wall by means of a sealing gun remains a major care of the manufacturers of such elements and of the users of this particularly practical sealing system, and this consideration has given rise to the appearance of a profusion of guide means of which the least that can be said is that these latter are costly and/ or not very effective and that, in point of fact, there still exists at the present time a deficiency in the achievement of perfect perpendicularity of fixing of pins, nails, etc. which are fired into a hard and compact material by means of a sealing gun.

The present invention is intended to overcome this deficiency and has for its object the new article of manufacture which consists of a particularly effective and inexpensive guide means for a sealing element having a front stem and a rear head, the rear extremity of which is already provided with a guiding arrangement or device, the said new guide means being characterized in that it consists of a cap which is fitted at least to a partial extent over the front portion of the rear head of the sealing element and the periphery of which has at least three points inscribed Within a circumference which is substantially co-axial with the sealing element and which substantially corresponding to the bore of the gun barrel.

The arrangement is preferably such that the thickness of the wall of that portion of the guide means which is fitted over the front of the head is so designed that the said portion substantially fills the annular space between the said head and the internal wall of the gun barrel.

In a first form of embodiment of the new guide means, this latter consists of a small polygonal plate pierced with a hole having a diameter which permits the said plate to be force-fitted over the stem of the sealing element and to be brought into abutment with the head of the said element, the said small polygonal plate being designed so that each summit at least of the polygon can be bent back against the said head and thus be inscribed within the circumference which substantially corresponds to the bore of the gun barrel.

In this embodiment of the new guide means, this latter is further characterized by the following features and combinations thereof:

The small plate has the shape of a regular polygon which has concave sides so as to form relatively projecting summits, thereby giving the said plate the appearance of a star having short points which alone are intended to be bent back;

The small plate has a thickness such that those portions thereof which are bent back against the head of the pin fill up radially the space between the pin head and the gun bore;

The bent-back portions of the small plate have a certain elasticity;

The small plate is made of a material which is readily destructible at the time of impact of the said plate against the material which is intended to receive the sealing element;

The small plate is made of aluminum sheet or brass sheet.

In another form of embodiment of the guide means, this latter consists of a substantially frusto-conical cap which is advantageously of plastic or of like material, the said cap being fitted over the rear part of the stem of the sealing element and advantageously terminating in arms which fit over the front portion of the head of the said element.

In the case in which the head of the sealing element is threaded, screw-threads are formed on the internal surfaces of the arms and are intended to come into engagement with the screw-threads of the said head.

Further particular features and characteristics of the invention will be brought out by the description which follows below and which relates to a number of forms of embodiment of the new guide means, the said forms of embodiment being given solely by way of non-limitative examples and illustrated diagrammatically in the accompanying drawings, in which:

FIG. 1 is a front view of a first form of embodiment of the guide means;

FIG. 2 is a sectional view showing the small plate of FIG. 1 which is crimped onto a pin placed inside the barrel of a sealing gun;

FIG. 3 is a view looking on the end of FIG. 2;

FIG. 4 is a view taken in perspective of an alternative form of embodiment in which the guide means is a cap of plastic;

FIG. 5 is a view in longitudinal cross-section of the guide means of FIG. 4 which is fitted on a sealing pin;

In the embodiment illustrated in FIGS. 1 to 3, the guide plate 1 of brass or aluminum is of square shape and the sides 2 thereof are slightly concave so that the summits or corners 3 have the appearance of the points of a star.

The hole 4, which is located at the centre of the plate 1, has a diameter such that there can be force-fitted therein the front portion 5a of a pin 5 having a rear head 5b.

There has been illustrated in the drawings a sealing and centering plug 6, of plastic for example, which is fitted over the rear of the pin head, the said head being assumed to be threaded.

In order to associate a pin of this type with the guide plate 1, the portion 5a of the pin is fitted inside the hole 4 of the plate 1 until this latter comes into abutment with the pin head 5b, the corners 3 of the said plate being bent back by crimping, for example, so as to be pressed against the said pin head until the maximum cross-section of the combined assembly of pin and plate substantially corresponds, as shown in FIGS. 2 and 3, to the bore of the barrel C of the sealing gun.

Experience has shown that perfect perpendicularity of fixing of pins can be obtained by means of a guide means of this type, irrespective of the nature of the material into which the said pins are driven. Moreover, the guide plate is self-destroyed at the moment when it strikes against the material into which the pin is driven.

In the alternative form of FIGS. 4 and 5, the guide means consists of a cap 7 of substantially frusto-conical shape and preferably of plastic, the said cap comprising four arms 8, on the internal faces of which are formed threads 9 which, as can be seen in FIG. 5, are intended to be brought into engagement with the threaded portion of the head 5b of the pin 5, on the stem 5a of which is fitted the cap 7.

The new guide means for the sealing elements such as pins, nails, etc. has proved to be particularly etfective and the sealing devices which are fitted with the said guide means accordingly become new articles of manufacture.

It is apparent that the examples of construction of the new guide means which are illustrated in the drawings and described in the foregoing have been given solely by way of indication without implied limitation and that any detailed modification can be made therein without consequently departing either from the scope or the spirit of the invention.

It accordingly follows in particular that the guide plate of FIGS. 1 to 3 could be either triangular, pentagonal, hexagonal, etc. or even circular. In this latter case, the said plate could have the appearance of a cup which is fitted over the head of the pin. Moreover, the cap of FIGS. 4 and 5 could have a number of arms 8 other than four.

What I claim is:

A fastener intended to be fired with an explosively actuated power tool and comprising: a stem having a pointed front end; a rear head forming one piece with 20 said stem and having a greater diameter than that of said stem; and guiding means consisting of a substantially frusto-conical cap made of destructible material and having a central opening wherein is forcibly engaged the stem and whose periphery has arms fitted over the front part of said head, wherein the head is threaded, whereas the internal surfaces of the arms in contact with the head have a thread which is in engagement with the thread of the head, the periphery of said cap having at least three points which are inscribed within a circumference substantially coaxial with the fastener and whose diameter substantially corresponds to the calibre of the power tool.

References Cited by the Examiner UNITED STATES PATENTS 2,676,508 4/54 Erickson. 2,853,914 9/58 Behrend.

FOREIGN PATENTS 1,100,553 4/55 France. 1,112,887 11/55 France.

743,808 1/5 6 Great Britain.

CARL W. TOMLIN, Primary Examiner.

EDWARD C. ALLEN, Examiner. 

